Bonete (Ilha Bela) Swell Statistics, Marzo: All Swell – Any Wind

This picture describes the variation of swells directed at Bonete (Ilha Bela) over a normal March. It is based on 2964 NWW3 model predictions since 2007 (values every 3 hours). The wave model does not forecast wind or surf right at the coastline so we have chosen the best grid node based on what we know about Bonete (Ilha Bela), and at Bonete (Ilha Bela) the best grid node is 17 km away (11 miles).

The rose diagram describes the distribution of swell directions and swell sizes, while the graph at the bottom shows the same thing but without direction information. Five colours represent increasing wave sizes. Very small swells of less than 0.5m (1.5 feet) high are shown in blue. These happened only 26% of the time. Green and yellow represent increasing swell sizes and red represents highest swells greater than >3m (>10ft). In each graph, the area of any colour is proportional to how often that size swell was forecast.

The diagram indicates that the prevailing swell direction, shown by the longest spokes, was SSE, whereas the the dominant wind blows from the E. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Bonete (Ilha Bela) and away from the coast. We combine these with the no surf category of the bar chart. To avoid confusion we don't show these in the rose graph. Because wind determines whether or not waves are clean enough to surf at Bonete (Ilha Bela), you can select a similar diagram that shows only the swells that were expected to coincide with glassy or offshore wind conditions. During a typical March, swells large enough to cause surfable waves at Bonete (Ilha Bela) run for about 74% of the time.

IMPORTANT: Beta version feature! Swell heights are open water values from NWW3. There is no attempt to model near-shore effects. Coastal wave heights will generally be less, especially if the break does not have unobstructed exposure to the open ocean.